1. Field of the Invention
The present invention relates to an image processing apparatus for performing image processing between a plurality of color image input units and a plurality of color image output units and more particularly to an image processing apparatus capable of processing, in an integrated manner, a color document comprising image elements fed from the plurality of color image input units, which image elements have different image attributes and to an image-attribute adjusting method.
2. Description of the Related Art
A document is generally formed of a plurality of image elements such as characters, diagrams and photographs, and the preparation and editing of these image elements are often made by executing a special application program corresponding to the kind of the element. When the image element is caused to undergo image processing, the application program used to prepare the element is normally employed for the image processing. Thus there is an environmental restriction in that the special application corresponding to the kind of the image element has to be relied upon in the process of preparing such a document.
When DTP is used to prepare a color document, proper printing is made after checking by design proof and color proof are carried out. In a case where correction or modification to the image element is required after the proper printing, that is, where satisfactory color reproduction is unobtainable, correction work will have to be done retroactively to the application used to prepare the image element due to the aforementioned environmental restriction even an editing process like color adjustment and a process without being accompanied by the preparation of a new image element, for example, are to be dealt with.
In this case, the image processing application is broadly classified into two categories: a pixel-to-pixel image data processing type and a descriptive type with the preparation of a row of processing contents with respect to image data. In other words, the first type is to cause image data to undergo direct processing; apart from the processing concerned, image data is saved in a buffer or the like before and each time the processing is performed and when the processing is canceled, the cancellation of such processing is fulfilled by restoring the image data thus saved.
In the second type, on the other hand, a thinning-out image (reduced image), not an original image, is caused to undergo processing in the course of editing, whereby not only response speed but also independence of processing contents is improved. Moreover, recovery is easy when the processing is canceled since the original image is not caused to undergo processing unless a special instruction is given in the course of editing.
In the aforementioned image processing application, the first type has the following problem: In the first type, the image processing time required becomes longer in proportion to image data capacity. In this case, a decrease in processing speed poses a serious problem particularly when an extremely large image is dealt with because data capacity grows larger with its dependence on image size, resolution, the number of colors and the like.
Moreover, neither of the above types are equipped with means of dealing with, in an integrated manner, a plurality of images prepared with different applications or means of pigeonholing and partially utilizing processing contents. This is because the processing contents have been defined as part of the image attributes and are manipulated by the applications.
Therefore, a linear flow is induced so that a layout is made after each image is completed and consequently the degree of freedom and flexibility of image processing are impaired, which constitutes a minus factor in document productivity.